Matilda de Clere

http://fmg.ac/Projects/MedLands/ENGLISHNOBILITYMEDIEVAL3T-Z.htm#dau...

Cawley (see above) *is* capable of making mistakes, and in this case I don't think he thought things through, or else relied too heavily on "traditional" secondary sources. It simply is not possible that Matilda was a Clare AND sister to a Treasurer of York - she most certainly was not and could not have been sister to Bevis/Bogo de Clare, the late 13th century benefice-hog. who would have been her great-grandson. Bogo de Clare, Clerk

There are no other recorded Clare treasurers of York in this time period.

(There are no recorded Clere treasurers either, but there was a William no-last-name who was treasurer from 1118-1122.) William, treasurer of York Minster - presumptively her brother. He is mentioned, with no family name, in charters and accounts 1218-1222. Succeeded as treasurer by 19 June 1222, by one William de Rotherfield. (There were three Williams active in the York ecclesiastical hierarchy circa 1220, per a charter of Archbishop Gray dated 3 Sep. 1220, witnessed by William 'the treasurer,' William 'Archdeacon of the East Riding,' and William 'Archdeacon of Richmond' - that last apparently being de Rotherfield and the other two being of unknown families.)

Extensive and inconclusive discussion here: https://groups.google.com/g/soc.genealogy.medieval/c/EDthyh06leQ